reverse_proxy.md

Reverse proxy guide

If you want to put MailCrab behind a reverse proxy, you can use the following configurations:

Nginx

server {
    listen 80;

    server_name <your server name>;

    location / {
        proxy_set_header Host $host;
        proxy_set_header X-Real-IP $remote_addr;
        proxy_set_header X-Forwarded-For $proxy_add_x_forwarded_for;
        proxy_pass http://<your MailCrab server>:1080;
    }

    location /ws {
        proxy_set_header Host $host;
        proxy_set_header X-Real-IP $remote_addr;
        proxy_set_header X-Forwarded-For $proxy_add_x_forwarded_for;
        proxy_http_version 1.1;
        proxy_set_header Upgrade $http_upgrade;
        proxy_set_header Connection "upgrade";
        proxy_pass http://<your MailCrab server>:1080;
    }
}

If you are using MAILCRAB_PREFIX, for example MAILCRAB_PREFIX=emails:

location /emails {
    ...
}

location /emails/ws {
    ...
}

Apache2

• For apache2 version 2.4.47 and later:

  Enable mod_proxy and mod_proxy_http. Then you can use the following snippet:

  <VirtualHost *:80>
      ProxyPass "/ws" "http://<your MailCrab server>:1080/ws" upgrade=websocket
  
      ProxyPass "/" "http://<your MailCrab server>:1080/"
      ProxyPassReverse "/" "http://<your MailCrab server>:1080/"
  </VirtualHost>

  If you are using MAILCRAB_PREFIX, for example MAILCRAB_PREFIX=emails:

  <VirtualHost *:80>
      ProxyPass "/emails/ws" "http://<your MailCrab server>:1080/emails/ws" upgrade=websocket
  
      ProxyPass "/emails" "http://<your MailCrab server>:1080/emails"
      ProxyPassReverse "/emails" "http://<your MailCrab server>:1080/emails"
  </VirtualHost>

• For apache2 version 2.4.46 and earlier:

  Enable mod_proxy, mod_proxy_http and mod_proxy_wstunnel. Then you can use the following snippet:

  <VirtualHost *:80>
      ProxyPass "/ws" "ws://<your MailCrab server>:1080/ws"
  
      ProxyPass "/" "http://<your MailCrab server>:1080/"
      ProxyPassReverse "/" "http://<your MailCrab server>:1080/"
  </VirtualHost>

  If you are using MAILCRAB_PREFIX, for example MAILCRAB_PREFIX=emails:

  <VirtualHost *:80>
      ProxyPass "/emails/ws" "ws://<your MailCrab server>:1080/emails/ws"
  
      ProxyPass "/emails" "http://<your MailCrab server>:1080/emails"
      ProxyPassReverse "/emails" "http://<your MailCrab server>:1080/emails"
  </VirtualHost>

Other reverse proxies

MailCrab is using 3 endpoints in its backend:

• /api for the messages.
• /ws for client-backend communication (using WebSocket).
• /static for assets.

Just proxy those 3 endpoints to the backend and it should work properly.

If you are using MAILCRAB_PREFIX, add the prefix before each endpoint: /<prefix>/{api, ws, static}